Grant-in-Aid for Scientific Research (A)
|Allocation Type||Single-year Grants|
|Research Institution||NIHON UNIVERSITY|
SAITO Tsuyoshi NIHON UNIVERSITY,SCHOOL OF DENTISTRY,PROFESSOR, 歯学部, 教授 (60059235)
YAMAMOTO Hiroshi NIHON UNIVERSITY,SCHOOL OF TECHNOLOGY,PROFESSOR, 理工学部, 教授 (90130632)
YAMAOKA Masaru NIHON UNIVERSITY,SCHOOL OF DENTISTRY,ASSITANT, 歯学部, 助手 (60182408)
KOMORI Norio NIHON UNIVERSITY,SCHOOL OF DENTISTRY,ASSITANT, 歯学部, 助手 (60153681)
AKASHI Toshikazu NIHON UNIVERSITY,SCHOOL OF DENTISTRY,LECTURARE, 歯学部, 講師 (80102606)
森川 良則 日本大学, 理工学部, 助手 (60239639)
|Project Period (FY)
1995 – 1997
Completed(Fiscal Year 1997)
|Budget Amount *help
¥19,000,000 (Direct Cost : ¥19,000,000)
Fiscal Year 1997 : ¥1,500,000 (Direct Cost : ¥1,500,000)
Fiscal Year 1996 : ¥5,900,000 (Direct Cost : ¥5,900,000)
Fiscal Year 1995 : ¥11,600,000 (Direct Cost : ¥11,600,000)
|Keywords||tooth mobility / periodontal charactaristic / damped natural frequency / elastic constant / viscous constant / damped oscillation system / 歯の打診 / 歯周組織の変化 / 減衰固有振動 / 歯の動揺 / 歯の共振 / 歯の槌打|
The measurment to tooth mobility has been recognized clinicaly as an important method to evaluate periodontal legament and other periodontal states. An objective attracted a lot of attention. In order to establish an objective evaluation method for periodontiume, including tooth mobility, this project study groupe has been developed an instrument "Damped Oscillation System" an studied dynamic parameter change (damped natural frequency, elastic constant, viscous constant and the ratio of elastic constant to viscous constant) by diff-erent conditon of Damped Oscillation including the position of sennsor, the size, shape and number of root model. And also, a comparative study with two commercial instrument, "perio-test" and "tooth mobility checker" were compleated, in advance to clinical use.
Results are followed :
1)In the case of moving the position of the detecing sensor horizontaly by hammer tappings from both horizontal and vertical directions, all values of the dynamic parameter decre
ased as the distance between the detecting sensor and the tooth model increased.
2)In the case of moving the position of the detecting sensor verticaly by horizontal tapping, the dynamic parameter increased as a distanse between the detecting sensor and the top of the tooth model increased, except the ratio of elastic constant to viscous constant. On the other hand, by vertical tapping, no significant change of all values of the dynamic parameter was recognized.
3)When the distance between the roots was altered, an increase in distance between the roots lowered the dynamic parameter. The comparison between parallel and perpendicular percussion showed a large difference.
4)When the location of the furcation area was altered, higher locations produced a lower dynamic parameter. There was no identifiable change regardless the ratio of elastic constant to viscous constant. There was also a significant difference between the result for paralleland perpendicular angle percussion.
5)As compared two commercial instrument, "perio-test" and "tooth mobilitychecker" which were able to evaluate the mobility in quantitative manner, it was shown that newly developed device, damped oscillation system, was able to grasp the periodontium characteristics by introducing dynamic parameters. Less